黏果酸浆

• 黍(glutinous millet; sticky grain)RADICAL
• 占(divination; fortune-telling)PHONETIC

Sticky glutinous rice grains cling tightly as if being held fast and unable to come loose.

• 酉(wine vessel; ferment)RADICAL
• 夋(slow manner; leisurely pace)PHONETIC

Fermenting alcohol produces sourness, which is exactly the character for sour.